Various conveyor arrangements have been provided for the purpose of placing granular or plastic materials, and concrete or the like, such as disclosed in prior Oury U.S. Pat. Nos. 3,151,732, 3,171,534 and 3,203,538. Another conveyor arrangement is shown in my copending application, Ser. No. 735,004, filed June 6, 1968. The presently disclosed conveyor system is particularly adapted for mounting on a wheeled vehicle having an extensible boom which can also be elevated and swung from side to side, and the boom carries part of the conveyor system so that the discharge end of the system can be adjusted by the operator of the vehicle to follow a wall form or the like, and elevated as the materials accumulate without interrupting the continuous flow of concrete from a delivery vehicle to the conveyor system and from the conveyor system to various positions of deposit.
One object of the invention therefore is to provide a design of conveyor system in which a lower conveyor is telescopically related to an upper conveyor and manipulated by the extensible boom, both conveyors being mounted on the boom and a supply conveyor being related to the upper conveyor so as to supply materials thereto continuously without interruption while the lower conveyor is being extended or retracted, and while the boom is being raised or lowered.
Another object is to provide a lower conveyor so mounted on an extensible boom that it can be extended and retracted with the boom, and additionally extended and retracted relative to the boom for maximum range of discharge end positioning.
Still another object is to provide a supply conveyor which is mounted on castered wheels and discharges into a swivel hopper, which in turn discharges onto the upper conveyor of the system, the caster wheels permitting positioning of the wheeled vehicle and thereafter swinging of the supply hopper to a suitable position for receiving materials from a supply vehicle.
A further object is to provide means for locking the caster wheels against castering so that the wheeled vehicle can be driven from one place to another with the supply hopper trailing behind it, the caster wheels being then unlocked for swinging the supply hopper to any suitable position for receiving materials.
Still a further object is to provide a swivel hopper mounted in alignment with the vertical axis on which the extensible boom swings, and an arrangement for readjusting the swivel hopper to align with that axis following a change in inclination of the extensible boom and the conveyors carried thereby.
An additional object is to provide supporting means for the upper and lower conveyors on the extensible boom so arranged as to permit various adjustments of the upper and lower conveyors in relation to each other and counteract cantilever action of the lower conveyor by properly adjusting the supporting means by extension or retraction of the extensible boom.
Another additional object is to provide track and roller connections between the upper and lower conveyors and between the extensible portions of the boom and the conveyors to permit the various desired extensible and retractable adjustments of the upper and lower conveyors in relation to each other.
Still another additional object is to provide quickly disconnectable connections between the conveyor system and the extensible boom of the wheeled vehicle so that the conveyor system can be removed by another crane or the like, and the wheeled vehicle and its extensible boom thereupon used in its normal capacity as a crane.
A further additional object is to provide automatic release means for a tremie at the outer discharge end of the lower conveyor so that upon the tremie becoming overloaded such release can occur.
Still a further additional object is to provide signal means and a circuit for stopping the conveyor system operable prior to automatic release of the tremie.